Another Speedo Question

[edub655321]

Ever since I got this car I have been having trouble with the speedometer. It usually works for a while after start up until something knocks it loose. I have sourced the problem to the bulb that you plug into the back cluster. Basically if I out my hand on this bulb and press it into the cluster hard when I am driving it works, and stays working until I hit a bump or something seems to jar it loose. The bulb seems to be soldered into place and is not burn out. Are my wires just bad and need to be replaced or do I need a new bulb?
Any help would be greatly appreciated.

Pics for clarity:
The "bulb"



And it Plugs into the hole on the far right side in this pic:

[Jean]

That bulb has nothing to do with speedo/odometer... probably wouldn't hurt to fix that ugly mess though.

[edub655321]

That's what I though the every time I push it in when the speedo stops, it starts working when you push it an hold it in. I'll play around with some of the other wire tomorrow and see. Thanks for the reply

[Jean]

Must be something else happening when you push that bulb in, take the cluster out and inspect everything.

[Schnitzer318is]

Sounds like you are closing a broken solder point or tracer when you are pushing that bulb in. See if flexing the back plastic has the same effect as pushing that bulb in.

[edub655321]

I tried pushing on the back today and did the same thing as pushing on the wire, so it isn't the wire it must be some solder on the board. Also it always works fine when the car is cold and the speedo will work fine for the first 20-30min, unless the car has been driven in the previous five hours. I plan on taking out and examining later tonight.

[edub655321]

The problem seems to be a bad resistor pictured here:


I guess the only thing now is to get a new board, unless it is possible to replace the resistor. It seems to be touching the board and maybe getting to hot? I wonder if bending it back will help. Also does anyone know if moto meter board and interchangeble with the vdo board or do you have to swap the SI board with it?

[Jean]

Your picture is blurry, are you sure the resistor is bad and not the solder joint or trace going to/from it? You can still replace it either way... what brand and part number is your main board . Is this an early cluster? vdo or moto?

I am not sure if the MAIN boards are interchangable, but the SI boards are.

[edub655321]

I put up a better pic above. Its an early model vdo board from a euro, don't think that matters, part number is 62111372255. The solder joint on the other side look fine, pic below. The plastic where the resistor was was a bit warm when I took it out. There is some white below the resistor and I can't see any visible breaks. I have a spare moto board but the way the tach hooks up is different so it seems like it would be easier to solder a new resistor in. Is there any way to find out the appropriate resistor?

[Jean]

"Its an early model vdo board from a euro, don't think that matters, part number is 62111372255" Well it does matter as the late model boards are completely different. Sorry, don't have any early ones on hand.

I would re-flow the solder joints, the traces look ok though. Even if you measure a burned out resistor you'll get a wrong reading.

[edub655321]

Thanks for the help. I have a late model moto board and housing but this tach won't fit in it. To reflow the solder do I just but it in a toaster oven and heat it, or do I have to add more solder to the joints?

[Jean]

Toaster oven?! You use a soldering gun, never used one I take it?

[edub655321]

I have but its been I while. I was looking at youtube videos where people where using toaster ovens to reflow. Thought It didn't seem like a good idea.